Relationships between fish, mouse and human group V and II CTLDs. Non-redundant set of CTLD sequences from known human and mouse CTLDcps classified as groups II and V, Fugu CTLDcps classified as group II, and putative killer cell receptor from Paralabidochromis chilotes (cKLR) were aligned with ClustalW. A consensus phylogenetic tree was built from 100 bootstrap trials using the protdist (with PAM distance matrix) and neighbor programs from the PHYLIP package. Black triangle shows position of cKLR. Bootstrap values higher than 40 are indicated.